On my Unifi network I've found locking devices to specific APs to sometimes not work well. I get to the same end point by having an SSID set up with only a single AP. No issues other than another SSID.
Ha ha. You'd think so. I have a BAF Haiku fan (2.4GHz) that is literally less than 10 ft from a U7 Pro XG. It likes to roam. I live in a Chicago SFH with lots of neighbors that like to blast the 2.4Ghz at both 20 and 40 MHz widths on channels other the 1, 6, 11. Lots of Eeros with auto channels and widths to make things even more complex.
On my UniFi system, I use a combined 2.4GHz and 5GHz WiFi WPA2 SSID for all IoT devices. For non-IoT devices, I use a combined 2.4GHz, 5GHz, 6GHz WiFi WPA2/WPA3 SSID. I do use UniFi's 'Lock to AP' feature for quite a few IoT devices to keep them associated with nearby APs. Some of those devices seem to always choose an AP on the other side of the house, resulting in low signal strength. I find the 'Lock to AP' feature works well for my environment.
You are correct. I have seen times where a older 2.4 GHz devices will randomly roam to another AP. For example my Eco Flow battery backup usually connects to the basement AP. Some times I find it connecting to the family room AP one floor up. Seems to be noise related but I do have my AP's for 2.4 GH set to medium power and spread out the 1, 6, 11 channels across the 4 AP's.
Another device is the Tablo TV Network TV Tuner/DVR. The closest AP to it is the 2nd floor AP but it will drop and then connect to the basement AP.
As others have stated depending on the "age/generation" of the 2.4 GHz device it may or may not work with AP Locking in Unifi. Also some devices don't like the "fast roam" feature thus I turned it off for the IoT network.
Poorly written network support is the primary reason the roam seems to happen. In a perfect would it look for the RSSI across all the AP's broadcasting the same SSID and connect to the best RSSI, but if retransmits become a problem it may jump to where there are lower retransmits and lower RSSI. This ballet of single strength and quality and rules and what to connect to isn't consistent.
Also many "cheap" devices will only lock to the first MAC of the AP with the SSID name and neve try to connect to the others. Once it joins the network and say that AP get's shut down the device will not connect to the next nearest. Saw this happen with Shelly WiFi devices a long time ago.
No, I had issues when trying WPA2/WPA3 on devices that only like WPA2. shouldn't be doesn't matter when what it is - is not working. I am not dropping my main network to WPA2 just because I have a few devices that just won't work. As to the 2.4 vs 5 ghz issue, my 3D printer will not even SEE the SSID for a mixed network.
The manufacturers of these devices know that they won't work and tell you ahead of time that you need a 2.4 ghz ONLY and WPA2 security. They know what their own hardware limitations are.
We aren't able to demand anything. Many of the manufacturers tell you up front. (That means it's a feature, not a bug from their perspective) We can not buy their products. But then that has its own issues.
Actually the way we demand better products is by not buying it so i don't see your point.
In todays world any new device or currently supported device should support wpa3. If you accept a new device today with wpa2 you are basically accepting no security. WPA2 has been cracked for a very long time and is less then minimal effort for security. That would actually prevent me from accepting a new product. I can accept that on some older gear if it has been around a while, but not anything relatively new.
WPA2 was rendered uselss back in 2017, so close to a decade ago. It shouls not be accepted in todays world.
I was even running wpa3 on my Google wifi gear before it got replaced. I think some devices needed to be reconfigured when i made the change, but they still worked.
That doesn't make any sense. 2.4ghz isn't different when the AP also broacasts the IP on 5ghz. They are seperate radios. The device has no way to know the AP is broadcasting it on 5ghz unless it has a way to acces the 5ghz band and scan for it.
If I was willing to pay twice the price, then yeah, I would not have a point. In many cases, that would mean just not being able to buy a particular class of device.
Maybe it does not. But it is reality. Again, you can google the issue. MANY 3D Printers specifically will not work on mixed networks. I already provided the excerpt directly from the manufacturer's manual for mine which explicitly states it will not work. And they were correct. The same goes for many of my other devices. Although although they might see it, they will absolutely not connect to a mixed network. If they do, they won't stay reliably connected.
This was not a signal strength issue, I checked with scanners at each location and more than enough signal strength to pull almost my full router bandwidth at each of the locations. This was even with my single AP in the center of my house. I upgraded to mesh to get more of a signal around the yard closer to the house. So now the signal is even stronger throughout the house and no difference.
It's possible that whatever antenna they are using on the client can't filter things out correctly. I just know they get confused, in some cases refuse to even see the mixed network.
I think your assumptions of how things should be ignores the potential lower quality network components of many of these IOT devices.
I just know it was enough of an issue for Linksys to post a troubleshooting article on it.
Maybe they could explain to you if you contact them. I would be interested in any responses (but it still won't change the reality of the situation)
Again, it is not the router/ap. I have run through several routers, and unsuccesfully tried to merge my wifi SSID at least once on every one I have. What has remained constant is the clients that were having trouble.
I read through most of this. I have three Unifi APs, Ch 1, 6, 11. Separate SSIDs for 2.5 and 5 Ghz. Several years ago there was a common SSID but the difficulty of dealing with IOT devices that are restricted to 2.5 forced the split. No issues since, mobile devices roam easily. Amazon's Firesticks oddly enough seem to be faster on 2.5. About 100 leased devices. I'm sure there are numerous old phones and stuff that have since been retired.
I think i should clarify i am not saying you are wrong or that what you are experiencing isn't true or valid.
How old is the gear you are talking about. Is it new or have you had it a while. Saying you have gone through several routers make me think these devices are older which can certainly explain why this still persists for you.
I have a Sovol SV07 Plus 3d printer with a fairly old board it seems to works fine atleast in my environment. What control board is in your 3d printer. The range it gets is horrible, but it does connect and works with my current AP placement.
I think this may relate to the shenanigans i mention earlier. I mentioned earlier when i got my first Air Gradient kit it had a issue with wifi not seeing pretty much anything. It was a cloned wemo D1 Mini microcontroller that was the problem. The folks at air gradient ended up replacing a bunch of them for folks because of the issue. I wonder how much of these problem devices are using cloned or recovered microcontrollers that are older tech. Probably most of them.
Hmm.... according to your prior comments, age shouldn't matter.
But, yes, Samsung Radiant R1's, which should work well with 5g just don't. They are circa 2016. Ecobee 4's don't like being on the mixed network either. They are ~2019 or 2019. Nest Camera Outdoor, prefer 2.4 ghz. Those are old enough to be out of warranty. They frequently drop on 5ghz (even with the recently purchased outdoor AP within 10 feet line of site). 3D Printer, don't know what card they put into it. Anycubic Kobra S1 - Designed and released in 2025 - Will not work on mixed mode at all. This is the one that would not even see the mixed network (I only tried because I wanted to see if the other user complaints were true - they were. To be fair, they stated as much on their website). Ecowitt requires 2.4 ghz to connect, but then you can change to mixed (per what I hear). Not sure what the actual release date was. But, it is only a year old.
So, a mix of old and new. But the issues were with new AP's then and now.
I acknowledged in the very first post that i did it in 2017 before i got Google wifi. The whole thread was about if it is still a ongoing issue. And if because of past experiences we recommend this even though it may not be relevant any more. Clearly there are occasions it may be. I do think some parts of the conversation dont make since like 5ghz impacting 2.4
It would be interesting to know the RSSi's of the devices you mentioned as having issues though are suppose to support 5ghz. I will repeat from my experience Ecobee 4 works fine with dual band. Mine has worked on SSID's combined since 2017 that is with google wifi and now Unifi U7 Pro Inwall AP's
As fas as the anycubic 3d printer That is very disappointing. That information just tells me to never get a 3d printer from that brand. Though the reception leaves something to be desired on my Sovol printer the old controller boars it uses is 2.4ghz only but works fine with the 5 and 6 ghz band on the same SSID. Worst case in could replace the control board witha pi running klipper if needed as well.
Age can't be ignored if you start to bring up devices that don't support WPA3. That should be a indicator of age in a way and there is no doubt any device in that situation will be a problem. That said i still think such devices dont belong on a network anymore.
No matter how you feel about it, clearly folks still deal with issues for a variety of reasons.some may not be directly relates to combining bands on the same SSID, but be fixed in a way by seperating the bands. The experience can change even with the same device based each of our unique environments.
To me this just means i wont feel comfortable making a suggestion to someone either way without reasonable testing of their environment with their devices. That kind of sucks, but is what it is.
I asked a couple of AIs and both suggested that it is not that the device is bothered directly by the 5Ghz since a 2.4Ghz device doesn't know that there is 5Ghz like you suggested. However, its that the AP sends a slightly different signal when using dual-band to the device that the device can't translate. Therefore, it won't connect. That is a way dumbed-down explanation from what I read online. If that's true, that would explain why you could be having no issues with a certain brand of a 2.4Ghz device on Brand A Access Point and someone else could have no luck w/ same brand of 2.4Ghz device on Brand B Access Point.
I think this entire thread boils down to not age of the device and the standards that were active at that time but this instead:
Did the vendor of the device follow the standards, does my WiFi vendor follow the coexist strategy of the WiFi alliance for previous standards?
When working with the FIRST Robotics program we use the latest Encryption standards for Robot Controllers along with moving away from 2.4 GHz to 5 GHz. The same WiFi technology standards used in medical gear. Encrypted connection handshake, etc. This standard was bult to "wall off" the other standards to make sure the devices are secure. But you can't do that in today's "messy world" of millions of variations of devices and implementations of "Open WiFi"
Yea.. I had checked with a AI as well to verify my thought prior to some of my statments above as well and it provided a conflicting answer. I was concerned about if something like that occured. So one of them is wrong and so is the problem with asking AI's. They tend to just make stuff up if they aren't sure.
I just checked again and this time using a different AI and got some more details with this AI that indicates it is related to the Beacon frames for management. Got to love AI.. Looks like it referes to RNR and Foast Roaming information elements provided when setting up the connection. There is also some other stuff as well.
I then asked it specifically if it says that the Information elements should cause it not to work, and it gave a interesting response. Basically it said it shouldn't, but if it has poorly written drivers/firmware then it may have a variety of issues.
It sounds like the real solution is we need all of these IOT devices to move from wifi4 to wifi6. I don't believe wifi5 worked on the 2.4ghz band if i remember right. It does make sense those devices operate on 2.4ghz for range.
That also supports what @ronv42 said above. They are not writting their drivers/firmware properly to parse the information in those management frames.
The last thing I asked the AI was what if any settings could be adjusted to help with those compatability issues and this is what it provided.
Turns out a few of them I already have setup on my general SSID that my IOT stuff is on. I checked my Unifi gear and for that network i have fast roaming off, and the Minimum data rate set to 24mbps. I do have band steering turned on and it set to wpa2/wpa3 security protocal though. I don't see a way to set 2.4 to only do wifi 4 and below though with my Unifi gear.
I would expect more from TPLink. The only way this problem makes sense is if the phone is litterly using its wifi discovery to program the device instead of connect to the device with its hotspot or bluetooth and then using what the device discovers. This is a really poor way to handle that since antenna difference can make a difference on what is scene much less the device having different capabilities.
It isn't a wifi problem perse based on the description of the problem, but a procedure problem.
a few factors come into play - i have 3 wifi bands, 2.4, 5 and 6 on my Access Points. the 2.4 and 5 are named the same in SSID. the 6 is different.
To connect a TPLink, you start a phone app and begin a process to program the unit - and at some point you get this 'we're going to switch to tp-04234' at that point it swaps to the units wifi broadcast , connects to it and loads it with the wifi from your phones settings. there is the problem. As it passes the wifi and password - it just circles the drain then fails. It never takes into account what band you were/are on at the time of the app start and thats the fail point imho. Not a lot of devices out there do all 3 bands - heck i've still got a robot vacuum that MUST be on 2.4.
Anyways - I didn't want to dis any particular vendor, I actually like tp link - just wanted others to keep in mind this weak spot that exists.
Ok so that pretty much confirms what i said above in that their process simply passes the SSID from the phone. It did no validation from the device to see what it can actually see. This is a failure of procedure on TP Links part. I dont they they are the only ones guilty of this. I have no problem calling them out for this. I suspect if you had your 6ghz band with the same ssid it would have worked.
During the setup do you have the option to change the ssid?
Doesn't all of that sound familiar.
